GB2429376A

GB2429376A - Communication Management System

Info

Publication number: GB2429376A
Application number: GB0616295A
Authority: GB
Inventors: Mitsuhiro Kubota
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2005-08-16
Filing date: 2006-08-16
Publication date: 2007-02-21
Anticipated expiration: 2026-08-16
Also published as: GB0616295D0; CN1929340A; CN1929340B; GB2429376B; JP2007053488A; JP4591697B2

Abstract

A communication management system includes: a control device for interconnecting terminals through a wired network to enable information transmission/reception; and, a management device for communicating with the control device and mobile terminals in a predetermined mobile communication area. The control device includes a management unit which, on receiving a request from one of the terminals 102a-c, grants a distribution right to the requesting terminal, and a distribution unit which, on receiving distribution information from the terminal having the distribution right, distributes that information to the management device and to a terminal without the distribution right. On receiving information from the terminal without the distribution right, the distribution unit transmits that information to terminals other than the one from which it was received. The management device also includes a communication control unit 107 for broadcasting or multicasting the distribution information to a mobile terminal 103a-c in a specified area upon its reception from the distribution unit.

Description

COI'1MUNICATION MANAGEMENT SYSTEM AND METHOD

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a communication management system and a communication management method capable of distributing information transmitted from a certain terminal to a plurality of terminals.

2. Description of the Related Art

There has conventionally been known a communication management system which distributes information transmitted froina certainterminaltoapluralityof terminals. Forexample, Japanese Patent LaidOpen Publication No. JP 1993-55980A discloses a mobile communication system which performs simultaneous multiple address transmission (information distribution). This mobile communication system includes terminal equipment for simultaneous multiple - address transmission use only, an exchange, a radio base station, and mobile stations.

Upon reception of a specific number from the terminal equipment, the exchange specifies a radio base station based on the specific number, and outputs an order for simultaneous multiple address transmission use only to the specified radio base station. Theradiobasestationthathas received the order performs simultaneous multiple address transmission to mobile stations present in its own service area.

However, in the mobile communication system described in Japanese Patent Laid-Open Publication JP1993-55980A, the terminal equipment for simultaneous multiple address transmission use only cannot communicate (i. e., transnit and receive information) with a plurality ofother terminals.

A third-generation cellular mobile communication system realizes transfer of information among a plurality of terminals.

Tobe specific, accordingtothethird-generationcellularmobile conirnunication system, IMS (IP Multimedia Subsystem) initiates a session among the plurality of terminals by SIP (Session Initiation Protocol). The SIP controls communication among the plurality of terminals. As a result, transfer of information is easily realized among the plurality of terminals.

Initiation and establishment of a session among many terminals by the SIP needs a great number of network resources.

The network resources are finite, so the number of terminals among which a session is initiated by the SIP is limited. RRC (Radio Resource Control) for managing infinite radio resources limits the number of mobile terminals which can be maintained in a state where an up- channel can be used. Thus, when information is transmitted and received among not so many terminals, a session can be initiated among the terminals by the SIP. However, when a certain terminal transmits specific information to a great many other terminals, initiation of a session among the terminals by the SIP is difficult.

Accordingly, when a session is to be always initiated among the terminals to be engaged in communication by the SIP, the following problem occurs. In other words, it is difficult for any one of the plurality of terminals engaged in information transfer with one another with a session having been initiated by the SIP to transmit specific information to a great many terminals including yet other terminals.

SUMMARY OF THE flVENTION

An exeztplaxy feature of the preferred errbodiments of the present invention is to provide a comtruinicatiori managnent system and method which enable one of a plurality of terminals engaged in information exchange with one another to distribute specific information to imDbile terminals present in a specific xwbile communication area.

The present invention provides a communication management system, including: a control device for interconnecting a plurality of terminals through a communication network to enable information transmission/reception among the plurality of terminals; and a management device communicable with the control device and for communicating with a mobile terminal present in a predetermined mobile communication area, wherein: the control device includes a management unit for giving, upon reception of an information distribution right request from one of the interconnected terminals, an information distribution right to the terminal which has transmitted the request, and a distribution unit for distributing distribution information to the management device and the terminal having no information distribution right upon reception of the distribution information from the terminal having the information distribution right,'and for transmitting information to the

S I

terminals other than a terminal of an iriforniation transmission source upon reception of the information from the terminal having no information distribution right; and the management /jlevice includes a communication control unit for transmitting the distribution information to the mobile terminal in the predetermined mobile communication area upon reception of the distribution information from the distribution unit through one of broadcast and multicast.

Further, the present invention provides a communication management method carried out by a communication management system including: a control device for interconnecting a plurality of terminals through a communication network to enable information transmission/reception among the plurality of terminals; and a management device communicable with the control device and for communicating with anobile terminal present in a predetermined mobile communication area, the method including: an information distribution right request receiving step of receiving, by the control device, an information distribution right request transmitted from one of the interconnected terminals; an information distribution right giving step of giving, by the control device, upon reception of the information distribution right request, the information distribution right to the terminal which has transmitted the request; an information input step of receiving, by the control device, information from the terminal having no information distribution right; an information transmission step of transmitting, by the control device, the information received in the information input step to the terminal other than the terminal having no information distribution right; a distribution information receiving step of receiving, by the control device, distribution information from the terminal having the information distribution pight; an information distribution step of distributing, by the control device, the distribution information received in the distribution information receiving step to the management device and the terminal having no information distribution right; and a transmission step of transmitting, by the management device, upon reception of the distribution information from the control device, the distribution information to the mobile terminal in the predetermined communication area through one of broadcast and multicast.

According to the present invention, when information is exchanged among terminals interconnected through a communication--network, one of the terminals can distribute specific information to many mobile terminals.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred features of the present invention will now be described, by way of exan1e only, with reference to the accompanying drawings, in which: FIG. 1 is a functional block diagram showing a configuration of a first exemplary embodiment of the present invention; FIG. 2 is a functional block diagram showing an example of an SIP server according to the first exemplary embodiment of the present invention; FIG. 3 is a functional block diagram showing an example of a management node according to the first exemplary embodiment of the present invention; FIG. 4 is a sequence diagram showing a proced1.re of initiating a session among a plurality of terminals by SIP according to the first exemplary embodiment of the present invrntion; FIG. 5 is a sequence diagram showing a procedure of distributing information by broadcast or multicast according to the first exemplary embodiment of the present invention; FIG. 6 is a sequence diagram showing a procedure of changing a service providing area according to the first exemplary embodiment of the present invention; FIG. 7 is a diagram showing an example of a display screen according to the first exemplary embodiment of the present invention; - - - FIG. 8 is a functional block diagram showing a configuration of a second exemplary embodiment of the present invention; FIG. 9 is a functional block diagram showing an example of a BM-SC according to the second exemplary embodiment of the present invention; and FIG. 10 is a sequence diagram showing a procedure of initiating a session among a plurality of terminals by SIP according to the second exemplary embodiment of the present invention.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Exemplary embodiments of the present invention will now be described in detail in accordance with the accompanying drawings.

<Configuration of -First Exemplary Embodiment> j FIG. 1 is a functional block diagram showing a configuration of a first exemplary embodiment of the present invention. In FIG. 1, a communication management system incaudes a wire communication network 101, a plurality of terminals 102 (102a, 102b, and 102c), a plurality of mobile terminals 103 (103a, 103b, and 103c), an SIP (Session Initiation Protocol) server 104, a management node 105, a CN (Core Network) 106, and an RAN (Radio Access Network) 107.

For example, the wire communication network 101 is a communication line network such as the Internet. Each o the terminals 102a, 102b, and 102c communicates with the SIP server 15- 104 via-the wire communication network 101. The number of terminals 102 are not limited to three, but can be changed as occasion demands.

The terminals 102a, 102b and 102 are identical in configuration and function. To prevent repeated explanation, the terminal 102a alone among the terminals 102a, 102b, and 102c will be described.

The terminal 102a is a communication terminal device having a function of transmitting/receiving data (information). The terminal 102a has afunctionof using, whena session is initiated withtheotherterminall02ormobileterminall03byslP, services for exchange (i. e., transmitting/receiving) a packet such as a voice, a video, or a text with the terminal with which the session has been initiated. It should be noted that the session among the terminals by the SIP is initiated and established by the SIP server 104.

Each of the mobile terminals 103a, 103b, and 103c /of the cellular mobile communication system is subordinate to a cell (mobile communication area) 108a or 108b controlled by the RAN 1O7, and has a function of receiving data transmitted from the RAN 107 through broadcast or multicast. In FIG. 1, the mobile terminals 103a and 103b are present in the cell 108a, and the mobile terminals 103b and 103c are present in the cell 108b.

The numbers of RAN's, cells, and mobile terminals are shown to be respectively 1, 2, and 3. However, these numbers are in no way limitative.

Each or one of the mobile terminals 103a, 103b, and 103c has a function of using services for exchange (i.e., transmitting/receiving) a packet such as a voice, a video, or a text with the terminal 102 or the other mobile terminal 103 when a session is initiated with the terminal by the SIP.

The SIP server 104 has a function of initiating a session among a plurality of communication terminals by the SIP, a function of transferring data received from the plurality of terminals to the management node 105, and a function of managing a right to execute information distribution (referred to as "information distribution right" hereinafter).

FIG. 2 is a block diagram showing an example of the SIP server 104 according to the first exemplary embodiment of the present invention. In FIG. 2, the SIP server 104 includes a communication unit 1041, a management unit 1042, and a distribution unit 1043. The distribution unit 1043 includes a session initiation unit 1044, and a distribution control unit 1045. - The communication unit 1041 is connected to th wire communication network 101 and the management node 105. The session initiationunit 1044 initiates and establishes a session among a plurality of devices (e.g., the plurality of terminals 102 and the mobile terminals 103) by the SIP. For example, the session initiation unit 1044 initiates and establishes a session among the plurality of terminals 102 by the SIP or between the plurality of terminals 102 and the mobile terminals 103, and connects the plurality of devices to enable information exchange (transmitting/receiving) among the plurality of devices.

In the present invention, the terminal device with which a session has been initiated and established by the SIP is referred toas a "session initiated terminal".

Upon reception of an information distribution right request for requesting an information distribution right from one of the plurality of session initiated terminals, the management unit 1042 gives an information distribution right to the session initiated terminal which has transmitted the information distribution right request. The management unit 1042 manages user information regarding users of the plurality of session initiated terminals, and provides user information regarding a user of the session initiated terminal having the information distribution right to the session initiated terminal having no information distribution right. For example, this user information is a user name of the session initiated terminal.

Each session initiated terminal receives the user information, and then dipplays the user information.

Upon reception of information (i.e., information to be distributed) from the session initiated terminal haviqg the information distribution right, the distribution control unit 1045 transmits the received distribution information to the management node 105 and the session initiated terminal having no information distribution right. Upon reception of information from the session initiated terminal having no information distribution right, the distribution control unit 1045 transmits the received information to the session initiated terminal other than the session initiated terminal which has transmitted the information (e.g., all the session initiated terminals other than the session initiated terminal which has transmitted the information). It should be noted that the distribution control unit 1045 does not transmit the information received from the session initiated terminal having no information distribution right tothemanagement node 105. This is because the information transmitted from the session initiated terminal having no information distribution right is equivalent to normal information exchange having been executed between the session initiated terminals.

Referring to FIG. 1 again, the management node 105 of the first exemplary embodiment of the present invention will be described. The management node 105 has a function of executing services for distributing data to the mobile terminal 103 corresponding to the cellular mobile communication system by broadcasting or multicasting, and a function of providing parameters regarding Q0C (Quality of Services) and a service area (i.e., communication area) to the CN 106.

FIG. 3 is a functional block diagram showing an example of the management node 105. In FIG. 3, the management riqde 105 includes a communication unit 1051, a communication area management unit 1052, an area information providing unit 1053, and a communication control unit 1054.

The communication unit 1051 is connected to the SIP server 104 and the CN 106. The communication area management unit 1052 manages a communication area t& which information can be distributed. For example, the communication area management unit 1052 manages a cell established by a previous contract among cells having functions of distributing data by broadcasting or multicasting as a communication area to which information can be distributed.

- - The colnmunicatiQn area management unit 1052 may manage the communication area to which information can be distributed based on a use situation of network resources of each cell. For example, the communication area management unit 1052 may manage a cell in which sufficient network resources are available as a communication area to which information can be distributed.

The communication area management unit 1052 manages the network resources.

Upon reception of an inquiry request of making an inquiry about the communication area to which information can be distributed from one of the plurality of session initiated terminals, the area information providing unit 1053 transmits area information indicating the information distributable communication area managed by the communication area management unit 1052 to the session initiated terminal which has transmitted the inquiry request.

Upon reception of information transmitted from the ess ion initiated terminal via the SIP server 104, the communication control unit 1054 distributes the received information to the mobile terminal103 present in the cell 108 by broadcast or multicast.

According to this embodiment, upon reception of area specifying information indicating a communication area (e.g., cell 108a) selected among communication areas indicted by area information from the session initiated terminal which has received the area information frornthe area informationproviding unit 1053, the communication control unit 1054 transmits the information transmitted from the session initiated terminal to the mobile terminal 103 resentin the communication area (e.g., cell 108a) indicated by the area specifying information. The area to be specified by the area specifying information may be plural.

Upon reception of the area specifying information from the session initiated terminal which has received the area information, the communication control unit 1054 transmits the area specifying information to the distribution contro.]. unit 1045 of the SIP server 104. The distribution control unit 1045 that has received the area specifying information distributes the area specifying information to the plurality of session initiated terminals. Upon reception of the area specifying information, the session initiated terminal displays the area specifying information.

Referring to FIG. 1 again, the description of the

functional block of the first exemplary embodiment of the present invention will be continued. The CN 106 and the RAN 107 have functions of transmitting data by broadcast or multicast.

The devices shown in the drawings have many well-known basic functions in addition to the functions described above.

Th basic functions are well known to those skilled in the art, and are not directly related to the present invention. Thus, detailed description of these basic functions will be omitted.

<Operation of First Exemplary Embodiment> Next, referring to the drawings, an operation of the first exemplary embodiment of the present invention will be described.

FIG. 4 is a sequence diagram showing a session initiation procedure among the plurality of terminals by SIP according to the first exemplary embodiment of the presentinvëTition. In FIG. 4, components similar to those of FIG. 1 are denoted by similar reference numerals. To simplify explanation, an operation when the terminals 102a and 102b become session initiated terminals will be described.

The terminal 102a executes step S401 upon reception of an instruction to start a session between the terminals 102a and 102b by SIP and an information distribution request to ask for information distribution by broadcast or multicast from a user. In the step S401, the terminal 102a starts a session by SIP. The terminal 102a executes step S402 after the start of the session by the SIP. In the step S402, the terminal 102a transmits an INVITE message indicating the start of the session between the terminals 102a and l02bbythe SIPand the information distribution request to the SIP server 104.

The SIP server 104 that has received the INVITE message executes step S403. In the step S403, the distribution ntrol unit 1045 of the SIP server 104 checks whether the INVITE message indicates the information distribution request. The session initiation unit 1044 of the SIP server 104 executes step S404 according to the start of the session between the terminals 102a and 102b by the SIP indicated by the INVITE message.

In the step S404, the session initiation unit 1044 transmits the INVITE message to the terminal 102b to initiate a session with the terminal 102b by the SIP. Based on the transmission/reception of such INVITE messages, the session is initiated between the terminals 102a and 102b by the SIP.

If the INVITE message transmitted from the terminal 102a indicates the info tibndistribution request iirthe step S403, the session is initiated between the terminals 102a and 102b by the SIP, and then the distribution control unit 1045 executes step S405.

In the step S405, the distribution control unit 1045 requests the management node 105 to secure resurces for executingbroadcastormulticast (i.e., makes a resource request).

The distribution control unit 1045 transmits an inquiry about an information distributable communication area (i.e., information distributable area inquiry) to the management node 105. This inquiry contains access information of the terminal 102a.

The management node 105 executes step S406 upon reception of the resource request and the information distributable area inquiry. In the step S406, the area information providing unit 1053 of the management node 105 checks the information distributable area and reserves resources by using the communication area management unit 1052.

The area information providing unit 1053 executes step S407 after checking the information distributable area and reservation of the resources. In the step S407, the area information providing unit 1053 transmits distributable area information indicating the checked area (e.g. , cells 108a and 10].08b) totheterntinal 102a. Thisdistributableareainformatjon contains access information of the management node 105. The distribution control unit 1045 of the SIP server 104 executes step S408 upon reception of the distributable area information addressed to the terminal 102a. In the step S408, the distribution control unit 1045 of the SIP server 104 transmits the distributable area information to the terminal 102a.

Upon reception of the distributable area information, the terminal 102a displays the received area information in a display unit (not shown). A user of the terminal 102a, i.e., a sending user, selects a distribution area (e.g., cell 108a) to which information is distributed among the displayed distributable areas, and inputs a selection result to the terminal 102a.

The terminal 102a executes the step S409 upon reception of the selection result. In the step S409, the terminal 102a transmits distribution area specifying information indicating the selected distribution area (e.g., cell 108a) to the management node 105. The distribution control unit 1045 of the SIP server 104 executes step S410 upon reception of the distribution area specifying information addressed to the management node 105. In the step S410, the distribution control unit 1045 of the SIP server 104 transmits the distributi9n area specifying information to the management node 105.

The management node 105 that has received the distribution area specifying information executes step S411. In the step S4]1, the communication control unit 1054 of the management node secures resources necessary for executing information distribution in thedistributionarea (e.g., cell 108a) indicated by the distribution area specifying information by using the communication area management unit 1052. In other words, a link is established in a service area within the cellular communication network. Further, after securing the resources to complete an information distribution preparation, the communication coto1_u it 1054 transmitsapreparatiori completion notification containing the distribution area specifying information to the terminal 102a.

The distribution control unit 1045 of the SIP server 104 executes step 5413 upon reception of the preparation completion notification. In the step S413, the distribution control unit 1045 transmits the preparation completion notification to the terminals 102a and 102b between which the session has been initiated by the SIP.

Upon reception of the preparation completion notification, the teiininals 102a and 102b displays the area specifying information contained in the preparation completion notification in the display unit. For example, the terminals 102a and 102b display the area specifying information as service area information. It should be noted that the service area information indicates the same area as long as there is no change.

The SIP-session initiated terminals can exchange (transmitting/receiving) a packet such as a voice, a video, or a text. Upon acquisition of the information distribution right, the session initiated terminal having the information distribution right can distribute information to the mobile terminal present in the cell belonging to the service area (i.e., the specified distribution area) indicated by the service area information by the broadcasting or multicasting function of the cellular communication system.

FIG. 5 is a -sequence diagram showing a procedure of distributing information selected by the sending user by broadcast or multicast according to the first exemplary embodiment of the-present nventThn: InFIG. 5 components similar to those of FIG. 1 are denoted by similar reference numerals.

When the user of the terminal 102a which is the session initiated terminal wishes to execute information distribution by broadcast or rnulticast, step S501 is executed. In the step S501, an information distribution start button (not shown) of the terminal 102a is pressed by the user of the terminal 102a.

The terminal 102a executes step S502 after the pressing of the information distribution start button of the terminal 102a. In the step S502, the terminal 102a transmits an information distribution right request to ask for an information distribution right to the SIP server 104.

The SIP server 104 that has received the information distributionrightrequestexecutesstepS5O3. InthestepS5O3, the management unit 1042 of the SIP server 104 checks whether a terminal (i.e., terminal 102b in-the example of FIG. 5)(other than the terminal 102a among the plurality of SIP-session initiated terminals has had the information distribution right.

If the session initiated terminal other than the terminal 102a has\no information distribution right, the management unit 1042 returns an OK message to the terminal 102a to give the information distribution right to the terminal 102a. Additionally, the management unit 1042 stores right providing destination information indicating the terminal to which the information distribution right has been given.

On the other hand, the management unit 1042 of the SIP server 104 returns an NG message to the terminal 102a when the session-initiated terminal other tharithé termirJTT02a has already had the information distribution right, in other words, when the other session initiated terminal has executed information distribution by broadcast or multicast. In this case, no information distribution right is provided to the terminal 102a.

Upon reception of the OK message from the management unit 1042 in the step S503, the user of the terminal 102a judges that the user can distribute information to a desired service area.

On the other hand, upon reception of the NG message from the management unit 1042, the user of the terminal 102a judges that the user cannot distribute information to the desired service area and waits for a while.

Next, the management unit 1042 of the SIP server 104 executes step S504 after the information distribution right has been given to the terminal102a in the step S503. In the step S504, the management unit 1042 notifies ongoing distribution information indicating ongoing use of information distribution services to the terminal (in this case, terminal 102b) session-initiated with the terminal 102a by the SIP. The management unit 1042 provides user information (i.e., sender information) regarding the user of the terminal 102a which has obtained the information distribution right to the other terminal (inthiscase, terminal 102b) session-initiatedwiththeterminal 102a by the SIP.

Upon reception of the ongoing distribution information, the terminal 102b displays an ongoing distribution icon indicating the ongoing use of the information distribution services in the display unit. Similarly, upon recepti-on of the sender information, the terminal 102b displays the received sender information in the display unit.

When watching the display to judge permission of information distribution to the desired service area, the user of the terminal 102a sets information (hereinafter, referred to as "distribution data") to be distributed by broadcast or multicast at the terminal 102a. After the setting of this distribution data, the terminal 102a executes step S505. In the step S505, the terminal 102a transmits the distribution data to the SIP server 104.

The SIP server 104 executes step S506 upon reception of the distribution data. In the step S506, the distribution control unit 1045 of the SIP server 104 checks a transmission source (i.e., sender) of the distribution data, and transfers thereceiveddataaccordingtoacheckingresult. Tobe specific, the distribution control unit 1045 executes steps S507 an S508 when the transmission source of the distribution data is a terminal having an information distribution right. On the other hand, when the transmission source of the distribution data is a t\erminal having no information distribution right, the distribution control unit 1045 executes the step S508 alone without executing the step 5507.

For example, if the distribution right providing destination information stored in the management unit 1042 indicates the sender of the distribution data, the distribution control unit 1045 judges that the sender of the distribution data is the terminal having the information distribution right.

If-the distributionright providing desti-nation- nformation is not matched with the sender of the distribution data, the distribution control unit 1045 judges that the sender of the distribution data is not the terminal having the information distribution right.

In the step S507, the distribution control unit 1045 transfers the received distribution data to the management node 105. The management node 105 executes step 5509 upon reception of the distribution data. In the step S509, the communication control unit 1054 of the management node 105 checks a mobile cornmuniation area (i.e., distribution service providing area) indicated by the area specifying information, executes distribution scheduling, and distributes the received distribution data to the mobile terminal 103 present in the service providing area via the CN 106 and the RAN by rnulticasting or broadcasting.

- In the step S508, the distribution control unit 1045 transmits the distribution data to the terminal (in this case, terminal 102b) sessioninitiated with the sender terminal 102a by the SIP. The distribution control unit 1045 may transmit the distribution data to the sender terminal 102a. Thus, the SIP server 104 forwards data onlytransmitted fromthe user having the information distribution right to the management node 105.

In two-way packet communication for mixing voice and video data provided from a plurality of users in a conference system or the like, the distribution control unit 1045 transfers data only transmitted from the session-initiated terminal having the information distribution right to the management node 105.

To stothe information ditr bution executed-by broadcast or inulticast, the user of the terminal 102a presses the information distribution button of the terminal 102a again. The terminal 102a transmits a distribution end request to the SIP server 104 according to this pressing. Upon reception of the distribution end request, the management unit 1042 of the SIP server 104 returns an OK message to the terminal 102a to obtain the information distribution right provided to the terminal 102a again, and to delete the right providing destination information indicating the terminal 102a. Upon reception of the OK message fromtheSlPserver 104, the terminal 102a finishes thedisplaying of the ongoing distribution icon.

Upon reception of the distribution end request, the management unit 1042 of the SIP server 104 transmits a distribution end notification to the terminal (in this case, terminal 102b) session-initiated with the terminal 102a by the SIP. The terminal 102b that has received the distribut4on end notification finishes the displaying of the ongoing distribution icon and the sender information.

FIG. 6 is a sequence diagram showingaprocedure of changing a service providing area of the &nformation distribution according to the first exemplary embodiment of the present invention. In FIG. 6, processes similar to those of FIG. 4 are denoted by similar reference numerals, anda description thereof will be omitted. The procedure of changing the service providing area will be described below mainly by way of a process different from that of FIG. 4.

When the user of the terminal 102a wishes to change the - - -information dsT iitió e vie oidqareLthe user of the terminal 102a inputs an inquiry to ask for an information distributable communication area at the terminal 102a. Upon the entry of the inquiry, the teiminal 102a executes step S601.

In the step S601, the terminal 102a transmits the inquiry to the management node 105 to make an inquiry about the information

distributable area.

The SIP server 104 executes step S602 upon reception of the inquiry addressed to the management node 105. In the step S602, the distribution control unit 1045 of the SIP server 104 transmits the received inquiry to the management node 105. The inquiry contains access information of the terminal 102a. The management node 105 executes the step S406 upon reception of the inquiry. Thereafter, the steps S407 to S413 shown in FIG. 4 are carried out.

FIG. 7 shows an example of a display screen of the terminal 102 and the mobile terminal 103 according to the first exenplary embodiment of the present invention. In FIG. 7, an ongoing distribution icon 7011, sender information 7012, and service area information 7013 are displayed in a display screen 701.

According to this exemplary embodiment, upon reception of information from the session initiated terminal having the information distribution right, the SIP server 104 recognizes the information as distribution data, and transmits the distribution data to the management node 105 and the other session initiated terminal having no information distribution right.

Upon reception of information from the session initiated terminal having no information distribution right, the SIP server- 104 transmits the information to the session initiated termifother than the session initiated terminal of the information transmission source (e.g., all the session initiated terminals other than the session initiated terminal which has transmitted the information). Upon reception of the distribution data from the SIP server 104, the management node 105 distributes the distribution data to the mobile terminal 103 by broadcast or inulticast.

Accordingly, the session initiated terminal can change an information distribution destination according to the presence of the informationdistributionright. Tobe specific, the session initiated terminal can exchange information with the other session initiated terminal irrespective of the presence of an information distribution right, and distribute information to the other session initiated terminal arid the mobile terminal 103 present in the selected cell 108 once an information distribution right is obtained. f The management node 105 transmits the received distribution data to the mobile terminal 103 by broadcasting or multicasting. Accordingly, information to be distributed (i.e., distribution data) can be distributed to the mobile terminal 103 with limited network resources.

As described above, if a need arises to distribute specific information to a great many mobile terminals while exchanging information with the other session initiated terminal, the session initiated terminal selects a mobile communication area for information distribution so that it can distribute the information to a mobile terminal in the mobile communication area.- -As apparent_from the foregoing, -the session initiated terminal first engaged in the information exchanging may be a mobile terminal. The information distributed to the mobile terminal is transmitted to the other terminal first initiated in session. In other words, the information distributed by obtaining the information distribution right is transmitted to the other session initiated terminal first engaged in the information exchanging and the mobile terminal in the selected mobile communication area.

According to this exemplary embodiment, the SIP server 104 manages user information regarding the users of the plurality of session initiated terminals, and provides user information regarding the user of the session initiated terminal having the information distribution right to the session initiated terminal having no information distribution right. In this case, a user who has distributed the information can be specified. Thus, for example, when distribution of improper or erroneous information is found, the distribution of the information can be stopped by ousting an information sender of an information distribution right. As a result, for example, information dis\tribution can be controlled in emergency.

According to this exemplary embodiment, the management node 105 manages the information distributable communication area, and provides information of the distributable area to the session initiated terminal which has made an inquiry upon reception of the inquiry about the information distributable communication area. Additionally, upon reception of area specifying information indicating the selected communication area from the terminal which has rece vedthe dis-t-r-i- butable area information, the management node 105 distributes the information receivedfromtheSlPserver 104 tothemobileterminall03present in the selected communication area. Accordingly, the user of the session initiated terminal can designate a communication area to which information is distributed. Thus, the user of the session initiated terminal can provide proper information to the mobile terminals present in each communication area.

According to this exemplary embodiment, upon reception of the area specifying information indicating the selected communication area from the session initiated terminal which has received the distributable area information, the management node 105 transmits the area specifying information to the SIP server 104. Then, the SIP server 104 transmits the area specifying information received from the management node 105 to the plurality of session initiated terminals. Thus, the user of:the session initia-ted terminals can easily understapd the communication area to which the information has currently been distributed.

According to this exemplary embodiment, the SIP server 104 initiates a session by the SIP, and interconnects the plurality of session initiated terminals to enable information exchange among them. In this case, for example, the session initiated terminal corresponding to the third generation cellular mobile conirnunication system can transmit specific information to a great many mobile terminals while it exchanges information with the other session initiated terminals.

Furthermore, according to this exemplary embodiment, as the séssïon initiated terminal- having----the information distribution right can be switched, information can be distributed from a plurality of places by broadcast ormulticast.

<Configuration of Second Exemplary Embodiment> Next, a second exemplary embodiment of the present inventionwilibe described. FIG. 8 isa functionalblockdiagram showing a configuration of the second exemplary embodiment of the present invention. In FIG. 8, components similar to those of FIG. 3. are denoted by similar reference numerals, and description thereof will be omitted. This exemplary embodiment is aimed at an information communication system in which the present invention is applied to a system using a code division multiplex system such as the CDMA (Wideband-Code Division Multiple Access). In FIG. 8, as compared with FIG. 1, the SIP server 104 and the management node 105 are changed to a PoC server 803, an INS core 802, and a EM-SC (Broadcast Multicast Service Centre) 801.

An example in which the present invention is applied to a push-to-talk over cellular (P0C) in the thirdgenerationmobile communication system wrii be described. The PoC realizes a one\.way communication service of a transceiver or the like, and quick communication between two people or among a group.

A multimedia broadcast multicast service (MBMS) is provided as a method for executing broadcast ormulticast service in the third generation mobile communication system.

In the MBMS, the BM-SC 801 manages a broadcast function and a inulticast function. According to the MBMS, to realize efficient information distribution, the BM-SC 801 separately -uses TPt)foTüsuiig arnmfl-channel to distribution information according to the number of mobile terminals present in the cell 108 and a point-to- point (P-t--P) for using an individual channels to distribute information.

FIG. 9 is a block diagram showing an example of the BM-SC 801 according to the second exemplary embodiment of the present invention. In FIG. 9, the BM-SC 801 includes a communication unit 8011, a communication area management unit 8012, an area information providing unit 8013, and a communication control unit 8014.

The communication unit 8011 is connected to the ThiS core 802 and the CN 106. The communication area management unit 8012 manages a communication area to which information can be distributed, For example, the communication area management unit 8012 manages a cell established by a previous contract among cells equipped with functions of distributing data by broadcast orim.lticast as a communication area to which informaton can be distributed.

The communication area management unit 8012 may manage the communication area to which information can be distributed based on a use situation of network resources of each cell. For example, the communication area management unit 8012 may manage a cell in which sufficient network resources are available as a communication area to which information can be distributed.

The communication area management unit 8012 manages the network resources.

Upon reception of an inquiry of making an inquiry about the communication area to which information can be distributed from one of a plurality of sssioniniiated terthinaThtffe area information providing unit 8013 transmits distributable area information indicating the information distributable communication area managed by the communication area management unit 8012 to the session initiated terminal which has transmitted the inquiry.

Upon reception of distribution data transmitted from the session initiated terminal via the P0C server 803, the communication control unit 8014 transmits the received distribution data to a mobile terminal 103 present in the cell 108 by broadcast or multicast.

According to this exemplary embodiment, upon reception of area specifying information indicating a communication area (e.g., cell 108a) selected among communication areas indicted by the area information from the session initiated terminal which has received the distributable area information from the area information providing unit 8013, the communication contrql unit 8014 distributes the distribution data to the mobile terminal 103 present in the communication area indicated by the area specifying information.

Upon reception of the area specifying information from the session initiated terminal which has received the distributable area information, the communication control unit 8014 transmits the area specifying information to the IMS core 802. The INS core 802 serves as the SIP server, and distributes the area specifying information to the plurality of session initiated terminals upon reception of the area specifying information. Upon reception of the area specifying information, the session initiated terminal displays-the- are-a-- speci-fying information. The communication control unit 8014 separately uses P-t-M and P-t-P according to the number of mobile terminals present in the cell 108.

Referring to FIG. 8 again, the description of the

configuration of the second exemplary embodiment of the present invention will be continued. The IMS core 802 has a function of managing a session by the SIP. Upon reception of an information distribution right request for requesting an information distribution right from one of a plurality of devices with which a session is initiated by the SIP (i.e., session initiated terminals), the IMS core 802 provides the information distribution right to the session initiated terminal which has transmitted the information distribution right request.

The IMS core 802 manages user information regarding users of the plurality of session initiated terminals, and provides user information regarding a user of a session initiated te,rininal having an information distribution right to a session initiated terminal having no information distribution right. For example, this user information is a user name of the session initiated teriiinal. Each session initiated terminal displays the receiveduser inf ormation upon reception of the user information.

The P0C server 803 has a function of managing a user talking right, and a function of giving a talking right to a user who requests talking.Upon reception of distribution data from the session initiated terminal having the information distribution right, the P0C server 803 distributes the distribution data to the BM-SC 801 and the session initiated terminal having no information distditinight - Upon reception of information from the session initiated terminal havingno inf orination distribution right, the PoC server 803 transmits the received information to the session initiated terminal other than the session initiated terminal which has transmitted the information. The PoC server 803 does not distribute information received from the session initiated terminal having no information distribution right to the BM-SC 801.

<Operation of Second Exemplary Embodiment> Next, referring to the drawings, an operation of the second exemplary embodiment of the present invention will be described.

FIG. 10 is a sequence diagram showing a session initiation procedure among the plurality of terminals by the SIP in PoC services according to the second exemplary embodiment of the present invention. In FIG. 10, components similar to those of FIG. 8 are denotedby similar reference numerals, anddescription thereof will be omitted. To simplify explanation, an operation in which terminals 102a and 102b serve as session initiated terminals will be described.

To execute communication by the PoC, the terminal 102a executes step SlOOl upon reception of an instruction to start a session among the terminals 102a and 102b and the P0C server 803 by the SIP and an information distribution request to ask for information distribution byMBMSfroma user. In the step SlOOl, the terminal 102a starts a session by the SIP. The terminal 102a executes step 51002 after the start of the session by the SIP. In the step S1002, the terminal 102a transmits an INVI.TEmessage indicating the statbf the etonTamong-the terminals 102a and 102b and the PoC server 803 by the SIP and the information distribution request to the IMS core 802.

The IMS core 802 that has received the INVITE message executes step S1003. In the step S1003, the IMS core 802 checks whether the INVITE message indicates the information distribution request. The IMS core 802 executes step S1004 in response to the start of the session among the terminals 102a and 102b and the PoC server 803 by the SIP indicated by the INVITE message. In the step S1004, the IMS core 802 transmits an INVITE message to the P0C server 803 to initiate a session with the PoC server 803 by the SIP.

The P0C server 803 that has received the INVITE message executes step S1005. In the step S1005, the PoC server 803 transmits an INVITE message to the IMS core 802. The IMS core 802 that has received the INVITE message from the P0C server -803 executes step-S1006. In the step S1006, the IMS cifre 802 transmits an INVITE message to the terminal 102b.

A session is initiated among the terminals 102a and 102b and the P0C server 803 by the SIP based on transmission/reception of\sucli INVITE messages.

If the INVITE message transmitted from the terminal 102a indicates an information distribution request in the step S1003, after a session is initiated among the terminals 102a and lO2b and the PoC server803 by the SIP, the IMS core 802 executes step S1007. In the step S1007, the IMS core 802 transmits an inquiry to make an inquiry about an information distributable area by the MBMS to the BM-SC 801. Also, the IMS core 802 requests the- 3M-SC 801 to ecure resources for executing information distribution.

The procedure regarding the information distribution area thereafter is similar to that of the first exemplary embodiment.

To be specific, steps S1008, S1009, S1013, and S10l4 executed by the BMSC 801 corresponds to the steps S406, S407, S411, and S4l2executedbythemanagementnode lOSof FIG. 4, respectively.

Steps SlOlO, S1012, and S1015 executed by the IMS core 802 correspond to the steps S408, S410, and S413 executed by the SIP server 104 of FIG. 4, respectively. Step S1011 executed by the terminal 102a corresponds to the step S409 executed by the terminal 102a of FIG. 4.

Voice communication by the P0C is enabled between terminals having established SIP session (i.e., the session initiated terminals). Once provided with an information distribution right, any one of the session initiated terminals can distribute information to-mobile terminals present in a cell belonging to a service area indicated by service area information by the MBMS.

Since the P0C permits one-way communication, the number of talking user is always one.

When wishing to execute information distribution by the MBMS, the user of the session initiated terminal presses an information distribution button of the session initiated terminal. An example in which the terminal 102a is a session initiated terminal will be described below. Upon pressing of the inf ormation distribution button, the terminal 102a transmits an information distribution right request to the IMS core 802.

The IMS core 802 that has received the information -d-i-stribution right request checks whether a session-initiated terminal other than the terminal 102a among the plurality of SIP-session initiated terminals has had an information distribution right. If all the session initiated terminals have no information distribution right, in other words, if the other session initiated terminals execute no information distribution by broadcast ormulticast, the IMS core 802 returns anOKmessage to the terminal 102a to give an information distribution right to the terminal 102a. In this case, the IMS core 802 notifies informationtoidentifyauserhaviflgaflirlfOrmatiOfldiStribUtiOn right to the PoC server 803.

On the other hand, the IMS core 802 returns an NG message to the terminal 102a when the session initiated terminal other than the terminal 102a has had the information distribution right, in other words, when another session initiated terminal has executed information distril =ution by broadcast or multicast.

In this case, rio information distribution right is provizied to the terminal 102a.

Upon reception of the OK message from the IMS core 802, the user of the terminal 102a judges that the user can distribute infprmation to a service area. On the other hand, upon reception of the NG message from the IMS core 802, the user of the terminal 102a judges that the user cannot distribute information to the service area to wait for a while.

After the information distribution right has been given to the terminal 102a, the IMS core 802 notifies ongoing distribution information indicating ongoing use of information distribution services to the terminal with which a session is initiated with the-terminal 102a by the SIP (e.g., the terminal 102b). The INS core 802 provides user information (i.e., sender information) regarding the user of the terminal 102a which has obtainedthe informationdistributionrighttothe terminal 102b.

Upon reception of the ongoing distribution information, the terminal 102b displays an ongoing distribution icon indicating the ongoing use of the information distribution services in the display unit and the received sender information.

The PoC server 803 manages a talking right of the PoC services. If the user having the information distribution right notifiea by the INS core 802 is not matched with the user having the PoC talking right, the PoC server 803 transmits distribution data received from the session initiated terminal (in this case, terminal 102a) used by the user having the information distribution right to the other session initiated terminal (in this case, terminal 102b). The PoC server 803 may distribute the distribution data received from the terminal 102a to the terminal 102a of a distribution source.

On he other hand, if the user having the information distribution right notified by the IMS core 802 is matched with theuserhavingthePoCtalking right, thePoCserver 803transfers the distribution data received from the session initiated terminal (in this case, terminal 102a) used by the user to the other session initiated terminal (in this case, terminal 102b) and the BM-SC 801. The PoC server 803 may distribute the distribution data received from the terminal 102a to the terminal 102a of the distribution source.

Upon reception of the distribution data from the PoC sever 803,the-BM-SC 801 checks acommuritcation area- (i;e.,service providing area) indicated by area specifying information. Then, the BM-SC 80]. separately uses P-t-M and P-t-P according to the number of mobile terminals 103 in the checked area, and distributes the distribution data to the mobile terminals 103 present in the service providing area by broadcast or multicast.

To stop the distribution by broadcast or multicast, the user of the terminal 102a presses the information distribution button of the terminal 102a again. The terminal 102a transmits a distribution end request to the IMS core 802 in response to this pressing. Upon reception of the distribution end request, the IMS core 802 returns an OK message to the terminal 102a to obtain the information distribution right provided to the terminal 102a again and delete the right providing destination information indicating the terminal 102a. Upon reception of* the OK message from the INS core 802, the terminal 102a finishes the displaying of-the ongoing distribution icon.

Upon reception of the distribution end request, the INS core 802 transmits a distribution end notification to the terminal (in this case, terminal 102b) having an SIP session wih the terminal 102a. Upon reception of the distribution end notification, the terminal 102b finishes the displaying of the ongoing distribution icon and the sender information.

A procedure of setting and changing an MBMS providing area by the user is similar to that of FIG. 6. To be specific, the procedure of setting and changing the MBMS providing area is similar to that of FIG. 6 as long asthe SIP server 104 of FIG. - 6 is changed to the IMS core 802 and the management node 105 -of FI-G.---6 isharédTito..theBM-SC8O1. - According to this embodiment, upon reception of distribution information from the session initiated terminal having an information distribution' right, thePoC server 803 distributes the received distribution information to the BM-SC 801 and the session initiated terminal having no information distribution right. Upon reception of the distribution information from the session initiated terminal having no information distribution right, the PoC server 803 distributes the received distribution information to the session initiated terminal other than the session initiated terminal of the informationtransmission source (e.g., all the sessioninitiated terminals other than the session initiated terminal which has transmitted the information). Upon reception of the distribution information from the PoC server 803, the EM-SC 80].

transmits the received distribution information to the mobile teftiinal 103 by broadcast or multicast.

Accordingly, the session initiated terminal can change an information distribution destination according to the presence of the information distribution right. Tobe specific, the session initiated terminal can exchange information with the other session initiated terminal irrespective of the presence of an information distribution right, and distribute information to the other session initiated terminal and the mobile terminal 103 present in the selected cell 108 once it obtains the information distribution right.

The BM-SC 801 transmits the received distribution information to the mobile terminal 103 by broadcast ormulticast.

Acàrdi-flly th cived dtstribution information can be transmitted to the mobile terminal 103 with limited network resources.

Thus, the session initiated terminal can transmit specific information to a great many mobile terminals while exchanging information with the othersession initiated terminal.

According to this exemplary embodiment, the IMS core 802 manages user information regarding the users of the plurality of session initiated terminals, and provides user information regarding the user of the session initiated terminal having the information distribution right to the session initiated terminals having no information distribution right.

Accordingly, a user who has distributed the information can be specified. Thus, for example, when distribution of improper or erroneous information is found, the distribution of the information can be stopped by ousting an information sender of an information distribution right.- As a result, for exmple, distributed information can be controlled in emergency.

According to this exemplary embodiment, the BM-SC 801 manages the information distributable communication area, and provides area information indicating a managed communication area to the session initiated terminal which has made an inquiry upon reception of the inguiryabout the information distributable communication area transmitted from one of the plurality of session initiated terminals.

Additionally, upon reception of area specifying information indicating the selected communication area from the session initiated terminal which has received the distributable area -information, ---thè BMSC80ltTräiismits thëdistribution information received from the P0C server 803 to the mobile terminals 103 present in the selected communication area.

Accordingly, the user of the session initiated terminal can designate a communication area to which information is distributed. Thus, the user of the session initiated terminal can provide proper information to mobile terminals present in each communication area.

According to this exemplary embodiment, upon reception of the area specifying information indicating the selected communication area from the session initiated terminal which has received the distributable area information, the 3M-SC 801 transmits the area specifying information to the PoC server 803.

Then, the PoC server 803 transmits the area specifying information received from the BH-SC 801 to the plurality of session initiated terminals. Thus, the user of the session initiated terminals can easily understand the communicatin area to which the information has currently been distributed.

According to this exemplary embodiment, the IMS core 802 initiates a session by SIP between the plurality of terminals ancthe PoCserver 803, and interconnects thepluralityof session initiated terminals to enable information exchange among them.

In this case, for example, the session initiated terminal corresponding to the third generation cellular mobile communication systerncan transmit specific informationtoagreat many mobile terminals while the terminal exchanges information with the other session initiated terminals.

According to this exemplary embodiment, because the IMS core 802, the FcC server 803 and the BM-SC 801 are used, for example, simultaneous broadcast communication can be executed from the session initiated terminals connected to an IP network such as the Internet to the mobile communication network.

Further, simultaneous broadcast communication can be executed from the session initiated terminals connected to the mobile communication network to the mobile communication network.

According to each of the foregoing exemplary embodiments, the mobile terminal 10,3 may serve as the session initiated terminal. The present invention may be used in a communication field such as a cellular mobile communication system which can utilize broadcasting or multicasting.

While the present invention has been described in its preferred embodiments, it is to be understood that the words which have been used are words of description rather than limitation, and that changes may be made to the invention without departing from its scope as defined by the appended claims.

Each feature disclosed in this specification (which term includes the claims) and/or shown in the drawings may be incorporated in the invention independently of other disclosed and/or illustrated features.

The text of the abstract filed herewith is repeated here as

part of the specification.

A coninunication management system includes: a control device for interconnecting terminals through a network to enable information transmission/reception; and, a management device for comrruinicating with the control device and mobile terminals in a -predetermined- mobile -con jnication area. The control device includes: a management unit for giving, upon receiving a request from one of the terminals, a distribution right to the requesting terminal; and, a distribution unit for distributing, upon receiving distribution information from the terminal having the distribution right, that distribution information to the management device and to a terminal without the distribution right, and for transmitting, upon receiving information from the terminal without the distribution right, that information to the terminals other than the transmitting terminal. The management device includes a communication control unit for transmitting the distribution information to the mobile terminal in a specified area upon reception of the distribution information from the distribution unit through broadcast or multicast.

This application is based on Japanese Patent Application No. JP 2005235947, filed on 16 August 2005, the content of which is incorporated into this application by reference.

Claims

1. A communication management system, coIrrising: a control device for interconnecting a plurality of' terminals through a cotununication network to enable information transmission/reception among the plurality of terminals; and, a management device able to communicate with the control device and with a mobile terminal present in a predetermined mobile communication area; wherein: the control device includes: a management unit for giving, upon receiving a request from one of the interconnected terminals, a right to distribute information to the terminal transmitting the request; and, --a distribution-unit for receiving distribution informa- tion from the terminal having the distribution right, and for distributing the distribution information to the management device and to a terminal not having the distribution right, and for transmitting, upon receiving information from a terminal not having the distribution right, that information to terminals other than the one from which it was received; and the management device includes: a corrununication control unit for transmitting through either broadcast or multicast, upon receiving the distribution information from the distribution unit, the distribution information to the mobile terminal in the predetermined mobile communication area.

2. The system according to claim 1, wherein the management unit manages user information regarding users of the plurality of terminals, and provides, to a terminal not having the distribution right, user information regarding a user of the terminal having the distribution right.

3. The system according to claim 1, wherein the management device further includes: a communication-area management unit for managing mobile communication areas to which information is distributable; and, an areainformation providing unit for providing to a terminal, upon reception of an inquiry transmitted from that terminal regarding the informationdistributable areas, area information indicating the informationdistributable mobile communication areas managed by the communicationarea management unit; and wherein the communication control unit transmits, upon reception of area-specifying information indicating a mobile communication area selected by the terminal to which the area information has been provided, the distribution information received from the distribution unit to mobile terminals present in the selected mobile communication area.

4. The system according to claim 3, wherein: the communication control unit transmits the area-specifying information to the distribution unit; and, the distribution unit distributes, to the plurality of terminals, the area-specifying information received from the communication control unit.

5. The system according to claim 1, wherein the distribu- tion unit initiates a session among the plurality of terminals by Session Initiation Protocol (SIP), and interconnects the terminals to enable information exchange among the session-initiated terminals.

6. The system according to claim 5, wherein the control device coriprises a SIP server.

7. The system according to claim 6, wherein the management device corrprises a broadcast/multicast service centre.

8. A oinmuflication management method carried out by a communication management system including: a control device for interconnecting a plurality of terminals through a connunication network to enable information transmission/reception among the plurality of terminals; and, a management device cormiunicable with the control device and for communicating with a mobile terminal present in a predetermined mobile comrmmication area, the method including: an information-distributionright-request receiving step of receiving, by the control device, an information-distribution-right request transmitted from one of the interconnected terminals; an information-distribution-right giving step of giving, by the control device, upon reception of the information-distribution- right request, the information-distribution right to the terminal which has transmitted the request; an information-input step of receiving, by the control device, information from a terminal not having the distribution right; an information-transmission step of transmitting, by the control device, the information received in the information-input step to terminals other than the one from which it was received; a distribution-information receiving step of receiving, by the control device, distribution information from the terminal having the distribution right; an information-distribution step of distributing by the control device, to the management device and the terminal not having the distribution right, the distribution information received in the distribution-information receiving step; and, a transmission step of transmitting by the management device through either broadcast or multicast, upon reception of the distribution information from the control device, the distribution information to the mobile terminal in the predetermined coimn.ini- cation area.

9. The method according to claim 8, wherein: the control device manages user information regarding users of the plurality of terminals; and, the method further includes: a user-information providing step of providing, by the control device, to a terminal not having the distribution right, user information regarding a user of the terminal having the distribution right.

10. The method according to claim 8, wherein: the management device manages mobile communication' areas to which information is distributable; and, the method further includes: an inquiry-receiving step of receiving, by the management device, an inquiry about the information-distributable mobile communication areas transmitted from one of the plurality of terminals; an area-information providing step of providing by the management device, upon reception of an inquiry, area information indicating the information-distributable mobile communication areas to the terminal which has transmitted the inquiry; and, an area-specifying infoimiation-receiving step of receiving, by the management device; areaspecifying- information indicating a mobile communication area selected by the terminal to which the area information has been provided; wherein, in the transmission step, the management device transmits the distribution information received from the control device to the mobile terminals present in the mobile comnnninication area indicated by the area-specifying information.

11. The method according to claim 10, further including the steps of: transmitting, by the management device, the received area- specifying information to the control device; receiving, by the control device, the area-specifying inform- S ation from the management device; and, distributing, by the control device, the received area- specifying information to the plurality of terminals.

12. The method according to claim 8, further including a step of initiating, by the control device, a session axing the plurality of terminals by SIP, and interconnecting the terminals to enable information exchange among the session-initiated terminals.

13. A communication management method, including the steps of: Initiating, by a communication network control device, a session among a plurality of terminals interconnected through a communication network by SIP to enable information transmission! reception among- the terminals-, -. -- -- - --- - providing, based on a request from a mobile terminal that is one of the interconnected terminals and is in a cellular mobile communication system connected to the communication network, an information distribution right to the mobile terminal; transmitting distribution information to the communication network control device from the terminal to which the distribution right has been provided; transferring, by the communication network control device, the distribution information to the sessioninitiated terminal by SIP; transferring, by the communication network control device, the distribution information to the cellular mobile communication system; and, distributing, by the cellular mobile communication system, the distribution information to all mobile terminals in a designated communication area; wherein both communication among the session-initiated terminals by the SIP and distribution of information to the mobile corrunication terminals in a desired area of the cellular mobile communication system can be carried out.

14. A communication management device substantially as herein described with reference to and as shown in the accorranying drawings.

15. A comranication management method substantially as herein described with reference to and as shown in the acconpai'iying draWins. - -